Human iPSC-EV-loaded nanofiber stent coatings accelerate vascular repair by enhancing EGFR/HIF-1α signaling and...

Arterial disease management is shifting from antiproliferative drug-eluting stents toward approaches that restore endothelial function and modulate smooth muscle cell (SMC) behavior. Stem cell-derived extracellular vesicles (EVs) carry miRNAs that promote endothelial proliferation and migration while restraining aberrant SMC growth and inflammation. Here, human induced pluripotent stem cell (iPSC)-derived EVs were collected by ultracentrifugation and incorporated into 50:50 poly (lactic-co-glycolic acid) (PLGA 503) core-shell nanofibrous membranes, which were fabricated as stent coatings for sustained release to overcome rapid clearance and poor tissue retention. EVs derived from three independent iPSC lines all enhanced tube formation in human umbilical vein endothelial cells (HUVECs) under hypoxic and serum-starved conditions and revealed a trend toward reduced platelet-derived growth factor-BB (PDGF-BB)-induced smooth muscle cell (SMC) migration. The fabricated core-shell nanofibers enabled sustained EV release, maintaining therapeutic efficacy for 28 days. Small RNA sequencing (NGS) analysis demonstrated that EVs from these independent iPSC lines shared miR-148a-3p and members of the miR-92 family, which collectively accounted for more than 75% of the reads within the 25 top-expressed miRNA set. In vitro, iPSC-EVs enhanced HUVEC proliferation and survival signaling by downregulating the negative regulators ERRFI1 and VHL, which are specific targets of miR-148a-3p and the miR-92 family, thereby activating the EGFR and HIF-1α axes and driving downstream ERK1/2 and VEGF expression under hypoxic and serum starvation stress conditions. Concurrently, iPSC-EVs prevented PDGF-BB-induced SMC phenotypic switching by downregulating ROCK1, a target of miR-148a-3p, thereby inhibiting downstream AKT and ERK signaling and preserving contractile markers while suppressing the synthetic phenotype. In vivo, the iPSC-EV-functionalized scaffolds significantly accelerated re-endothelialization and inhibited neointimal hyperplasia, evidenced by the upregulation of angiogenic factors (VEGF, CD31) and the concurrent suppression of pathological remodeling markers (α-SMA, MMPs) and inflammatory cytokines (IL-6, TGF-β1). Therefore, iPSC-EVs enriched with specific miRNAs and delivered via PLGA 503 core-shell nanofibers promote endothelial repair while suppressing SMC overgrowth, providing a promising strategy for vascular healing.